This invention relates to compressed air motors in general and, in particular to a new and useful motor having improved means for reversing the compressed air drive of a slidable piston.
More specifically, the invention relates to a compressed air motor, comprising, a cylinder, an axially movable piston, a piston rod, and a piston slide valve which is disposed parallel to the cylinder and reverses the compressed drive air and is in actuating connection with the piston by means of a snap-action device.
One known compressed air motor of this kind is intended to drive a double-acting piston pump as part of a high pressure paint sprayer. Its snap-action device comprises a control rod which penetrates the piston, protrudes into the hollow piston rod and has a perpendicularly projecting drive arm actuating the piston slide valve. The snap-action is obtained by means of two radially spring-loaded snap slides, below which, rollers, mounted to the driver, pass.
A disadvantage of this complicated design, among others, is that compressed air motors of different displacement in one type series almost always require special components suited to the particular motor type. Moreover, for larger piston diameters, the driver arm is particularly unfavorable because the friction losses caused by bending deformations increase beyond proportion as the driver's overhand, i.e., the piston diameter, increases.